Opiates are analgesic drugs derived from the opium poppy. The term 'opioids' includes both opiates (based on naturally occurring compounds) and synthetic compounds that act on opiate receptors.

Opioids are generally taken to produce a sense of wellbeing and to reduce the effects of stress and pain.

Opioids are addictive and habit forming. Regular use quickly creates tolerance leading the user to seek increasingly larger doses of the drug to achieve the same effect. Physical withdrawal effects, while very unpleasant, are rarely life-threatening.

Opioids are frequently injected. Harmful chemical contaminants used as cutting agents may include talc, glucose, quinine and strychnine.

Effects sought from the substance: Sense of wellbeing, reduction in stress and pain relief.

Long-term opioid use can result in gonadal suppression, reduced bone density and increased osteoporotic fracture risk.

Overdose: Opioids carry a high risk of lethal overdose. Overdose results in respiratory and cardiovascular depression and loss of consciousness which leads to death. Tolerance to opioids develops rapidly resulting in the use of increasing amounts of unknown drug purity, heightening the risk of accidental overdose.

Withdrawal: In the dependent person, withdrawal is uncomfortable, somewhat resembling influenza. Features include rhinorrhea, lacrimination, shivers and sweats, pilo-erection, sleeplessness, restlessness and agitation, abdominal and general muscular pains, diarrhoea and nausea.

Psychological presentations commonly associated with use (likely to resolve on cessation of substance use): Depression(24-27) and anxiety(11, 25, 28, 29).